Some Considerations Affecting the Design of Follow-Up Studies | ||||
The Egyptian Statistical Journal | ||||
Article 1, Volume 19, Issue 2, December 1975, Page 121-142 | ||||
Document Type: Original Article | ||||
DOI: 10.21608/esju.1975.315759 | ||||
View on SCiNiTO | ||||
Authors | ||||
Mindel C. Sheps; Ahmed Fathy Mahmoud Mustafa | ||||
Abstract | ||||
When a reasonable basis exists for postulating the distribution of risks (or of survival times) in a population, it may also provide a basis for choosing a desirable combination of sample size (n) and duration of follow-up (t). In studies of conception risk, if a Beta distribution of risks is assumed, the asymptotic precision and bias of maximum likelihood estimators of the parameters are improved by a moderate prolongation of t. Not surprisingly, the desirable value of t increases as the mean risk decreases, i.e. as the probability of "survival" beyond a fixed t increases. | ||||
Keywords | ||||
Design of Follow; Up Studies; Survival Times; Maximum Likelihood Estimators | ||||
Statistics Article View: 33 |
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